Stroke is the 3rd leading cause of death and the primary cause of severe, long term disability. Each year 795,000 Americans have a stroke and the annual costs to the economy are $57.9 billion. The vast majority of acute ischemic strokes are caused by a thrombus (blood clot) which occludes the blood vessel and stops blood flow to the brain. Tissue plasminogen activator (TPA), an agent that catalyzes the dissolution of blood clots, is the only effective, FDA-approved treatment for ischemic stroke. Unfortunately, TPA is associated with significant risks, delays in treatment, and is unsuccessful in up to 70% of patients at dissolving blood clots in sufficient time to protect the brain. There is a need for a safer, more effective therapy that facilitates early treatment, saves lives, reduces disability and lowers health care costs. In pre-clinical studies, we have shown that these goals might be achieved by a molecule that inactivates the major inhibitor of plasmin and, dissolves clots through a unique mechanism that avoids the risk of hemorrhage and neurotoxicity associated with TPA therapy. Following FDA guidance, we converted this molecule into a biologic drug candidate for stroke (stromab) that potently accelerates the dissolution of human clots. The goal of this Fast Track application is to move stromab further towards human trials by following FDA guidance to: 1) determine the optimal formulation and therapeutic time window for treatment, 2) produce and purify stromab under GLP conditions, 3) investigate the safety, pharmacokinetics and pharmacodynamics of stromab and, 4) submit an IND to the FDA.